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Conformational analysis and absolute stereochemistry of 'spongian'-related metabolites
(Elsevier Ltd, 2004)
New degraded and rearranged diterpenoids, 5-8, have been isolated from the Antarctic sponge Dendrilla membranosa. The structure and relative stereochemistry of these compounds were determined by spectroscopic data. The ...
Determinação da Estereoquímica Relativa de Pimaradienos Através de Produtos de Oxidação
(1997)
Relative stereochemistry determination of pimaradienes through oxidative products. Pimaradienes, including isopimaradienes, with an endocyclic double bond between C-9 and C-11 are uncommon compounds in nature. The diterpenoid ...
Detailed H-1 and C-13 NMR structural assignment and relative stereochemistry determination for three closely related sesquiterpene lactones
(JOHN WILEY & SONS LTD, 2008)
A complete analysis of H-1 and C-13 NMR spectra of the trypanocidal sesquiterpene lactone eremantholide C and two of its analogues is described. These structurally similar sesquiterpene lactones were submitted to H-1 NMR, ...
Stereochemistry determination by Powder X-Ray diffraction analysis and NMR spectroscopy residual dipolar couplings
(Wiley VCH Verlag, 2009-06)
For a new steroidal lactol, jaborosalactol 24, isolated from Jaborosa parviflora, NMR spectroscopy residual dipolar couplings and powder X-ray diffraction analysis independently gave the same stereochemistry at C23-C26. ...
A Conformational Model for MTPA Esters of Chiral N-(2-Hydroxyalkyl)acrylamides
(Hindawi Publishing Corporation, 2014-05)
The absolute stereochemistry of novel chiral N-(2-hycroxyalkyl)acrylamides prepared by a lipase-catalyzed resolution was successfully determined by 1H NMR of their MTPA esters. The method was validated for this particular ...
Determinação por RMN das configurações relativas e conformações de alcalóides oxindólicos isolados de Uncaria guianensis
(Sociedade Brasileira de Química, 2004-12-01)
Phytochemical studies with leaves of Uncaria guianensis resulted in the isolation of the oxindole alkaloids isomitraphylline (1), 3-isoajmalicine (2) mitraphylline (3), and isomitraphylinic acid (4). Structural assignments ...
Determinação por RMN das configurações relativas e conformações de alcalóides oxindólicos isolados de Uncaria guianensis
(Sociedade Brasileira de Química, 2004-12-01)
Phytochemical studies with leaves of Uncaria guianensis resulted in the isolation of the oxindole alkaloids isomitraphylline (1), 3-isoajmalicine (2) mitraphylline (3), and isomitraphylinic acid (4). Structural assignments ...
Stereochemistry of the carboxylation reaction catalyzed by the atp-dependent phosphoenolpyruvate carboxykinases from saccharomyces cerevisiae and anaerobiospirillum succiniciproducens
(ELSEVIER FRANCE-EDITIONS SCIENTIFIQUES MEDICALES ELSEVIER, 2008)
Stereochemistry of cyclopentane derivatives from (2,3)J(CH) dependence on dihedral angle (theta H-C-C-X)
(JOHN WILEY & SONS LTD, 2008)
The (2,3)J(CH) dependence on dihedral angle (theta H-C-C-X) for cyclopentane derivatives was investigated. We observed that the combined use of experimentally obtained (2,3)J(CH) values and the theoretically determined ...